In the manufacture of a semiconductor device, it is important to manage the shape of a pattern formed on a substrate in order to maintain desired quality. This pattern is measured by various devices. A small angle X-ray scattering device using small angle X-ray scattering (SAXS) has been developed as one of pattern shape measurement devices.
However, in the small angle X-ray scattering device according to the related art, a periodic structure that is virtually set is simplified to some extent on the basis of an expected structure. Therefore, it is impossible in reality to completely match the actual pattern having a complicated structure that is partially constricted with a periodic structure that is virtually set. For this reason, when there is a large difference between the periodic structure that is virtually set and the actual structure, it is difficult to measure the shape of the pattern with high accuracy.